The invention described in this application is described in Disclosure Document No. 089,393, the entire disclosure of which is incorporated herein by reference.
The present invention is concerned with a breathing tube for underwater activities. More particularly, the invention relates to improvements with respect to attachment means used to attach the breathing tube to a user's underwater mask.
One of the problems encountered with breathing tubes is that of their proper fixation in position for use and their disposition when not in use.
Numerous fixation systems have been designed for this purpose. The simplest consists in inserting the breathing tube under the fastening strap of the mask. However, this method proves inconvenient under many circumstances, and does not permit ready removal of the mouthpiece without a risk of displacing the mask as well, thus admitting water into the mask. It is also very uncomfortable to feel the constant pressure exerted on the head by the breathing tube which is pressed against the latter by the strap of the mask.
A second type of fixation consists in providing the tube with a pair of elastic rings joined together by an elastic band to be passed around the strap of the mask. This system is also inconvenient because the mouthpiece is kept fixed to the mask in a position which cannot be easily changed or adjusted, while it is often necessary to remove the mouthpiece from the user's mouth, as is required, for example, in changing from a mouthpiece breathing system to an auto-respirator system. Another drawback is that it tends to pull the hair of the user when he is not wearing a diving hood. The elastic rings generally do not last very long since they are pulled or stretched quite often, particularly when the mouthpiece of the breathing tube is inserted into the mouth or removed therefrom. Moreover, since these rings exert a gripping action on the tube and thus cannot be readily moved therealong for adjustment, the breathing tube is often misheld and/or mispositioned and, as a consequence, the tube undergoes vibration as the user swims and water may be more easily admitted thereinto. If the breathing tube is improperly positioned, the mouthpiece thereof has also a tendency of springing away from the mouth, resulting in inconvenience to the user as well as discomfort.
In some European countries, it has also been proposed to provide breathing tubes with a cord to be worn like a collar, and to fix the breathing tube in operative position to the fastening strap of the mask, whereas when not in use for a long period it may, for example, be placed in the belt. This cord is often in the way and dangerous to be worn around the neck. On the other hand, some divers put their breathing tube under their weight belt which is usually loaded and the tube often slips away. Others put it under the knife holding strap, along their leg; as a consequence, the breathing tube offers resistance to the diver's performance.